socket_recv
Pay attention! On some PHP version the MSG_DONTWAIT flag is not defined (see https://bugs.php.net/bug.php?id=48326)
socket_recvfrom
(PHP 4 >= 4.1.0, PHP 5)
socket_recvfrom — Recebe dados de um socket, conectado ou não
Descrição
int socket_recvfrom
( resource
$socket
, string $&buf
, int $len
, int $flags
, string $&name
[, int $&port
] )Aviso
Esta função é EXPERIMENTAL. O comportamento desta função, seu nome, incluindo toda documentação pode ser modificado sem aviso em futuras versões do PHP. Esta função deve ser usada por sua própria conta e risco.
Aviso
Esta função não está documentada; somente a lista de argumentos está disponível.
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User Contributed Notes
socket_recvfrom - [4 notes]
davide dot renzi at gmail dot com ¶
1 year ago
ryan_at_ryanfisher_dot_com ¶
6 years ago
DNS RELAY USING UDP SOCKETS
<?php
while(TRUE) {
$socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP);
if($socket === FALSE)
{
echo 'Socket_create failed: '.socket_strerror(socket_last_error())."\n";
}
if(!socket_bind($socketD, "0.0.0.0", 53)) {
socket_close($socketD);
echo 'socket_bind failed: '.socket_strerror(socket_last_error())."\n";
}
socket_recvfrom($socket,$buf,65535,0,$clientIP,$clientPort);
$stz = bin2hex($buf);
$tx = "";
for($i=0;$i<(strlen($stz)-26-10)/2;$i++)
{
$e = "00";
$e[0] = $stz[$i*2+26];
$e[1] = $stz[$i*2+27];
$f = hexdec($e);
if($f > 0 && $f < 32) $tx .= "."; else
$tx .= sprintf("%c",$f);
}
echo "$clientIP <".$tx.">\n";
$fp = fsockopen("udp://72.174.110.4",53,$errno,$errstr);
if (!$fp)
{
echo "ERROR: $errno - $errstr<br />\n";
}
else
{
fwrite($fp,$buf);
$ret = $buf;
$ret = fread($fp,667);
fclose($fp);
}
}
socket_send($socket,$ret,667,0);
}
?>
jaggerwang at gmail dot com ¶
5 years ago
I'm confused about the rerturn value of socket_recvfrom(), it said -1 when failed, but when I call like this:
if (($len = @socket_recvfrom($sock, $result, 32, 0, $ip, $port)) == -1) {
if ($this->_debug) {
echo "socket_read() failed: " . socket_strerror(socket_last_error()) . "\n";
}
return false;
}
variable $len = false, when I change the buffer length from 32 to 4096, it becomes right.
tsuna at tsunaquack d0t c0m ¶
8 years ago
This function is very handy when dealing with UDP connections, because it enables you to know who's the client who connected to your socket. Bear in mind that UDP doesn't care about the source of the connection, the packets may be annonymous or even faked. No check is required.
If you want to listen on an UDP socket and answer to the client, read my comment on socket_listen() -> http://www.php.net/manual/en/function.socket-listen.php